Over the last 50 years, orangutan populations have been in dramatic decline due to external factors like habitat fragmentation and poaching -- but a new study reveals the startling pervasiveness of their threat from humans. According to the results of a survey conducted in Indonesia, home to over 90 percent of the world's orangutans, the rates at which humans kill orangutans is higher than previously believed. In light of their findings, researchers are calling the serious threat humans pose on orangutans as "an uncomfortable truth that needs to be addressed."
The survey was conducted as a collaborative effort of 20 conservation organizations in 2009 and involved 6983 respondents from 687 Indonesian villages. Researchers were surprised to learn just how common human-orangutan conflicts took places, and just how often they resulted in a killing. According to the Associate Press, over half of the respondents reported having killed and eaten an orangutan in their lifetime.
From the study, published on PLoS ONE:
This survey revealed estimated killing rates of between 750 and 1800 animals killed in the last year, and between 1950 and 3100 animals killed per year on average within the lifetime of the survey respondents. These killing rates are higher than previously thought and are high enough to pose a serious threat to the continued existence of orangutans in Kalimantan.
There are believed to be only around 50 thousand orangutans left in the wild, increasingly isolated in fragmenting forests where run-ins with humans are more likely to occur. Despite the unexpected pervasiveness of orangutan killings in Indonesia, researchers were optimistic that educational programs could help to stem the tide -- now that the state of the problem is better understood.
"We used robust scientific methods to assess the social dimensions of orangutan conservation,” Erik Meijaard, one of the study's authors, tells the AP. “Unless we assume that most of the survey respondents lied, we have to accept the hunting issue as an uncomfortable truth that needs to be addressed if we want to save the orangutan.”